Subtract 81/28 from 21/15
1st number: 1 6/15, 2nd number: 2 25/28
21/15 - 81/28 is -209/140.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 28 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 15 × 28 = 420,
21/15 = 21 × 28/15 × 28 = 588/420 - Likewise, for the 2nd fraction, since 28 × 15 = 420,
81/28 = 81 × 15/28 × 15 = 1215/420 - Subtract the two like fractions:
588/420 - 1215/420 = 588 - 1215/420 = -627/420 - After reducing the fraction, the answer is -209/140
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